In the assembly of connectors to printed circuit boards such as D-connectors, suitable apertures are provided in the D-connector housing to secure the connector to the printed circuit board in predetermined locations. These locations are sited before securing the connector to the board. Traditionally various riveting means or other devices such as threaded screws with or without appropriate lock nuts and the like have been used to secure the connector to the printed circuit board. Further ultrasonic welding or heat staking have been used as well as conventional solderable eyelets.
A number of shortcomings have become evident as increasingly higher assembly rates are being demanded in the competitive setting of today's electronic industry. Moreover, with increasing miniaturization, the printed circuit boards may not be assembled with the same force being exerted such as on the rivets or the speed of machinery has been rather limited, e.g., for the riveting or ultrasonic welding operation.
Still further, in riveting the precise placement of each of the rivets is required, as well as the precise hammer and anvil coordination. Thus, riveting introduces unwanted assembly problems, especially where the entire assembly of the printed circuit board is completed prior to reflow soldering or infrared soldering. As a result, low force for securing the connectors to the printed circuit boards has been a desideratum. Thus, various other means have been proposed instead of traditional riveting and the like. These other assembly means have been such as, e.g., threaded sleeves in a printed circuit board or in the connector and a threaded bolt. Threaded connections require more expensive devices as well as manipulation of the connector housing. The threaded devices require reverse side securing means with sleeves. Hence, use of the threaded devices has introduced complications which are not amenable to high speed assembly, not only from the time element, but also the cost element for the threaded device or securing means.
Still further, when searching for the proper aperture with a threaded device, because of the necessity for a positive engagement, the tolerances are fairly low and positive aperture location by means of the threaded devices is harder to achieve.
In addition, any time tooling is employed which must act from the top and the bottom, precise location problems are multiplied, not only for the one side but also for the other, thus further complicating the tooling or machine necessary for the assembly.
In the fastener art a number of devices have been used, but these are not applicable to securing of electrical connectors to a printed circuit board. For example, U.S. Pat. No. 3,015,140 to Pender shows a clip with a fastener. The fastener is formed from the clip and is essentially square. Hence, for locating and positioning in a hole, it is not very suitable. Further, upon engagement in a round hole, very little area bears against the hole walls. Thus, the engagement is not positive and is apt to do damage to the hole walls.
For the above reasons, the device disclosed in U.S. Pat. No. 3,015,140 is not acceptable.